On Sunday (November 22), Justin Bieber attended the 2015 American Music Awards as one of the night's honored guests -- not only would he be picking up an award for Collaboration of the Year alongside Skrillex and Diplo (a fact he likely didn't know at the time), he was scheduled to close out the show with a medley performance of songs off his record-shattering new album Purpose. Biebs, newly minted fashion plate, hit the red carpet in an edgy t-shirt and jeans combo, but it wasn't the look's palpable DGAF attitude that had people up in arms, it was the fact that the reigning Prince of Pop would dare associate himself with rock deities Nirvana.

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The comments that followed his red carpet arrival in the "Heart-Shaped Box" tee were, in a word, unkind, accusing the 21-year-old -- who has been an internationally famous musician for the last seven years -- of not being a "real fan." The debate about whether Bieber is a poser or not became such a ~thing~ that it surfaced in an interview Harper's Bazaar did with his stylist Karla Welch.

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"Actually, it's not the first time he's worn a Nirvana tee," Welch explained to Bazaar. "We just have a nice collection of vintage tees, and then the tee he wore [at the AMAs] was actually Jerry Lorenzo's from Fear of God. [...] Of course he's a fan of Nirvana. I think it's so funny that all these people are up in arms. I'm sure Kurt Cobain would be like—I mean I can't speak for him, obviously—but I don't think he was so snotty or that he would diss anyone who appreciated his music. I think he understood that that is like the antithesis of music appreciation. It's so funny. But you know, fans are fans!"

Welch's story, of course, checks out, as just three weeks ago, Bieber was photographed wearing another Nirvana t-shirt -- this one slightly more subdued than the one he wore to the AMAs and obviously not at quite as high-profile a venue. But whether Justin wears a Nirvana shirt in private or on a red carpet shouldn't matter either way, and in neither situation are there any grounds to doubt whether he's a "legitimate" fan of the band.

Sure, his stylist could have just said he's a fan to smooth over the backlash, but it's her description of the situation that really seals the deal here for Bieber. "Jerry sent over the shirt like, 'Yeah let's wear the shirt' and we knew it was the 20th anniversary of the Nirvana AMAs, when they won," Welch told Bazaar, which is important because it's a connection that those pointing fingers at Bieber and goading that he "probably couldn't name five songs" by the band either didn't make or neglected to add.

Unfortunately for Biebs, this isn't even the first time this month he's come under fire for wearing another band's t-shirt. Two weeks ago, he wore a Metallica shirt on "The Ellen Degeneres Show" during his album release. As was the reaction to his Nirvana tee, fans of Metallica were similarly unhappy. However, what's different here is the storied mutual admiration between Bieber and Metallica.

In 2013, Noisey unearthed a video of Justin Bieber singing the guitar solo open to "Fade To Black," not because someone prompted him to, not because he had to as part of a collaboration with another artist, but because his guitar player Dan Kanter started the riff and Bieber joined in because he knew it by heart. As seems customary at this point, Metallica fans erupted about it, but in a subsequent interview with Q Magazine band members James Hetfield, Lars Ulrich and Robert Trujillo all admitted to being Beliebers themselves. While Bieber can't exactly get the same kind of stamp of approval from the late Kurt Cobain, he got something like the next best thing.

Courtney Love, for and about whom the song "Heart-Shaped Box" is written, came through for Bieber on Twitter with her personal co-sign of the singer and his shirt. So, if the actual artists can welcome Bieber unconditionally into their fandoms with open arms, why can't the other fans? Why is Bieber's legitimacy as a fan always in question? Why is it so hard for some people to believe that Justin Bieber -- a young man who has turned music into his life and livelihood -- would be a fan of two of the most influential bands of the last 30-some-odd years? What do you think he's listening to when he's thrashing around on skateboards in his free time?

I understand that Justin Bieber can be a polarizing figure, and as a fan of all three artists in question, I recognize that the music Bieber makes sounds nothing like Metallica or Nirvana. However, artists are allowed to be fans of other genres of music without making it themselves, and in an era where more different kinds of music are more easily accessible than ever, the bigger question -- to me -- would be: Why wouldn't Bieber have a favorite Nirvana track?